Authorities launched a nationwide manhunt Tuesday for Dubose and Rowe after the Georgia Bureau of Investigation said they fatally shot two guards on a prison transport bus before carjacking their way to freedom.

Putnam County Sheriff Howard Sills said the inmates fled from the bus near Eatonton, about 70 miles southeast of Atlanta. Sills said investigators were trying to determine how the killers got out of the inmate cage and into the driver's compartment.

On Tuesday evening, authorities at the Shelbyville Police Department told the GBI that they responded to a home invasion where Dubose and Rowe left two people tied up and fled the scene, GBI spokesman Steve Emmett said.

Authorities then chased the fugitives until they crashed their vehicle, Emmett said. The ensuing foot chase shut down Interstate 24, about 10 miles south of Murfreesboro.

The roadway was not expected to open up again until about 11 p.m.

Dubose is serving a 20-year sentence for armed robbery, aggravated assault and theft from a 2014 case. Rowe has been in prison since 2002 with convictions including armed robbery, possession of a firearm during a crime and aggravated assault.

The corrections department identified the victims as Christopher Monica, 42, who began working there in 2009, and Curtis Billue, 58, who would have marked his 10th anniversary with the department next month.

Since their escape, there had been numerous reported sightings, and authorities had offered a reward for their capture.